Portable small electronic apparatuses, such as digital cameras, portable phones, portable game machines, having plural functions and including sensors, such as angular velocity sensors and acceleration sensors, have been widely used in recent years. These apparatuses can be swung or revolved on purpose by users, and yet, they are equipped with cameras. When these apparatuses function as cameras, a motion sensor thereof can sense camera shake for correcting an image. This motion sensor senses a rather large motion caused by operating the apparatus, and also senses a rather small motion, such as camera shake. PTL 1 discloses a motion sensor that senses a large motion and a small motion.
FIG. 16 is a block diagram of conventional motion sensor 500 that senses a large motion and a small motion. Motion sensor 500 includes small-range motion sensor 501 for sensing a small acceleration, a large-range motion sensor 502 for sensing a large acceleration, selector 503 for switching between output signal S501 supplied from small-range motion sensor 501 and output signal S502 supplied from large-range motion sensor 502, signal processor 504 for processing output signal S503 supplied from selector 503, and controller 505 for controlling selector 503.
Controller 505 usually operates low range motion sensor 501; however, when an acceleration sensed by small-range motion sensor 501 exceeds a predetermined threshold, controller 505 operates large-range motion sensor 502.